Secondary lithium-ion batteries typically include an anode, an electrolyte, and a cathode that contains lithium in the form of a lithium-transition metal oxide. Examples of transition metal oxides that have been used in cathodes include lithium transition metal oxides that comprise various amounts of cobalt, nickel, and manganese. However, not all transition metal oxide cathode materials exhibit an optimal combination of high initial capacity, high thermal stability, and good capacity retention after repeated charge-discharge cycling.